1. Field of the Invention
The present invention relates to an ink-jet recording apparatus which performs a printing by ejecting ink droplets.
2. Description of Related Art
An ink-jet head included in an ink-jet recording apparatus which ejects ink droplets to a recording medium such as a recording paper is sometimes provided with a passage unit and an actuator. The passage unit has nozzles which eject ink droplets and pressure chambers which communicate with the nozzles. The actuator applies ejection energy to ink contained in the pressure chambers. The actuator applies pressure to a pressure chamber by changing a volume of the pressure chamber. Known as the actuator is one including a piezoelectric sheet which extends over a plurality of pressure chambers, a plurality of individual electrodes which are opposed to the respective pressure chambers, and a common electrode which is opposed to the plurality of individual electrodes with the piezoelectric sheet sandwiched therebetween and to which a reference potential is applied (see Japanese Unexamined Patent Publication No. 2002-36568 for example). In this actuator, a pulsed drive potential is applied to an individual electrode so that an electric field in a thickness direction of a piezoelectric layer acts on a portion of the piezoelectric sheet sandwiched between this individual electrode and the common electrode. As a result, in this portion, the piezoelectric sheet expands in the thickness direction. This changes a volume of a corresponding pressure chamber, and accordingly pressure as ejection energy is applied to ink contained in the pressure chamber.